DALLAS -- Environmental workers are setting traps all over Dallas County, collecting and testing mosquitoes, just in case West Nile infected ones spread their wings and the virus earlier than usual.

Authorities are particularly worried about vacant, foreclosed homes. Untended backyard pools become breeding grounds for mosquitoes. They are also a huge legal hassle for those in charge of mosquito control.

"Sometimes you have to go all the way to getting a search warrant before you can go on the property to determine if there is a problem and to treat it. So it can be real difficult," said Rodger Jayroe, City of Dallas.

By that time, mosquitoes can become a real health danger.

Tommy Harnett is convinced a stagnant pool in his neighborhood led to his West Nile encephalitis. "You get so weak, if I would shave, I would have to lay down from standing up that long," said Hartnett.

E-mail jstjames@wfaa.com